Abdulrahman A.M. Alghamdi* and Ahmed Mahmoud Al-Hejin

Biological Science Department, Faculty of Science, King Abdulaziz University, P.O. Box 80200, Jeddah 21589, Saudi Arabia

*Corresponding Author: Abdulrahman A.M. Alghamdi, Biological Science Department, Faculty of Science, King Abdulaziz University, P.O. Box 80200, Jeddah 21589, Saudi Arabia.

Received: November 27, 2025; Published: December 30, 2025

Abstract

The growing demand for new bioactive compounds in medicine, industry, and agriculture, coupled with the escalating issue of antimicrobial resistance, has intensified the search for extremophilic bacteria. Saudi Arabia hot springs represent underexplored environments were thermophilic Actinobacteria, adapted to high temperatures and wide range of pH levels, demonstrated remarkable metabolic capabilities and diverse biosynthetic gene clusters. This mini review compiles research (up to 2025) on the diversity, isolation, and biotechnological potential of thermophilic Actinobacteria derived from Saudi Arabian hot springs, including those in Jizan, Al-Lith, Aseer, and Tabuk. Whereas thermophilic Streptomyces produce potent antibacterial agents and antifungal agents' metabolites, while actinomycetes isolates produce thermostable enzymes (keratinase, gelatinase, chitinase, and lipase) relevant to textiles, food, and industrial applications. Endophytic actinobacteria obtained from plants growing near hot spring promote plant growth via phytohormones and nutrient mobilization, highlighting their agricultural potential in arid regions. However, previous studies have focused on Bacillus, leaving thermophilic Actinobacteria underexplored.

Keywords: Actinobacteria; Streptomyces; Bioactive Compound; Saudi Arabia; Hot Springs

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Citation

Citation: Abdulrahman A.M. Alghamdi and Ahmed Mahmoud Al-Hejin. “Thermophilic Actinobacteria from Saudi Arabian Hot Springs: Diversity, Bioactivity, and Bioprospecting Potential".Acta Scientific Microbiology 9.1 (2026): 39-46.

Copyright

Copyright: © 2026 Abdulrahman A.M. Alghamdi and Ahmed Mahmoud Al-Hejin. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.